Lorry-based concrete mixers are supplied with a movable discharge chute which can be positioned in various configurations to allow the discharge of concrete from the mixer drum. When not in use, and particularly when the vehicle is in transit, the chute is swung to a stowed position.
In the stowed position, there is the possibility that any loose stones within the mixer drum can bounce down the chute onto the road. As the stone will be moving at speed, it has the potential to bounce and strike another vehicle causing damage. This has been partially alleviated, in some cases, by the incorporation of a flap mounted to the chute. The flap is positioned to prevent stones leaving the chute during transit and is moved out of the way to allow for the discharge of concrete when required. One of the drawbacks of this arrangement is that this is known for the flap to be permanently located in the discharge position obviating the benefit of the chute; permitting stones to run down the chute during transit.
In the stowed position, there is also the possibility over time that the brackets holding the chute in the stowed position can come loose with the result that the chute can potentially swing away from the discharge position towards a vehicle following the mixer.